US rapper Nelly is refusing to take responsibility for the handguns, crystal meth, marijuana and drug paraphernalia found on his tour bus, claiming that several other people had access to the vehicle before the bust.

Speaking to TMZ, the hip hop star insisted that his only mistake was allowing random acquaintances to freeload.

"I feel the need to take responsibility for my choices in needing to be more aware of all the people I associate with and allow onto my property," he told the celebrity news site. "While my instinct of course, is to be accessible to my friends, fans and acquaintances, the last thing I would want to do is compromise the respect and admiration of my friends, family and fans."

Back in 2012, Nelly was arrested after authorities discovered marijuana, heroin and a loaded gun on his tour bus in west Texas. A member of his entourage was arrested after claiming responsibility for the items.

According to a police statement, the father-of-three's latest run-in with the law occurred after a state trooper "noticed an odour of marijuana emitting from the vehicle"

A search of the Prevost motor coach, uncovered five rocks of methamphetamine, a small amount of marijuana and drug paraphernalia and several handguns, including a gold-plated .50-calibre Desert Eagle pistol and a .500 Smith & Wesson magnum.

But the Hot in Here hit-maker's lawyer Scott Rosenblum said that "there had been 15-20 people that had access to the bus prior to the stop".

He added he was "extremely confident that when the facts come out, Nelly will not be associated with the contraband that was allegedly discovered".